The present invention relates to improving the heat resistance of chocolate or chocolate-type products so that they have a reduced tendency to deform or melt at elevated temperatures or to stick to the packaging material.
Chocolate products are usually thorough mixtures of liquid cocoa, cocoa butter, sugar, lecithin and possibly milk and flavouring substances. They therefore contain fatty substances which soften and melt between 30.degree. and 35.degree. C.
When articles which consist entirely or partly of these products are exposed to temperatures lying above the melting point of the aforesaid fatty substances, (i.e., temperatures occurring during the summer season or in tropical countries), they tend to lose their original shape and appearance, and become soft and unpleasant to handle. If they are wrapped, the surface of the article may adhere to the wrapper and may produce unsightly fat staining.
In the case of chocolate-type coatings intended to enrobe articles such as biscuits, confectionery, etc., the articles immediately lose their original appearance and are no longer suitable for consumption when they have been exposed to high temperature.
Different processes have been proposed in order to avoid the foregoing disadvantages, but the products obtained, although more resistant to the effects of high temperature, have an unpleasant taste and a perceptibly coarser texture than that of normal conched chocolate.
In European Patent Application Publication No. 0 189 469, there is claimed a method of increasing the viscosity of a chocolate composition containing cocoa butter so that said composition will be substantially non-flowable at a temperature well above the normal melting point of cocoa butter characterised in that it comprises mixing 0.2 to 5 wt % of a liquid polyol, which is selected from the group comprising glycerine, sorbitol, propylene glycol, mannitol, corn syrup and combinations and solutions thereof, with a chocolate mixture after it has been tempered. However, a disadvantage of this process is that the chocolate tends to set rapidly, e.g., from 40 to 60 seconds, and this allows very little time for the further processing of the chocolate, e.g., moulding into tablets of the desired shape or depositing a coating. A disadvantage of this method is that special additional equipment would be needed to incorporate the polyol at the latest possible time before further processing of the chocolate to prevent premature setting of the chocolate.
European Patent Application Publication No. 0 459 777 describes and claims a structured fat emulsion for incorporation into a confectionery coating as the fat ingredient thereof wherein:
a blend of a polyol component together with a fat component, said blend being a polyol-in-fat emulsion in which between about 2 and about 20 weight percent, based on the total weight of polyol-in-fat emulsion, said polyol component is emulsified within said fat component, whereby said structured fat emulsion effects a time-delay in the development of enhanced heat resistance and retardation of bloom development in a confectionery coating formulation when the formulation is subjected to setting conditions to form a set confectionery coating, and whereby these properties are substantially latent until the confectionery coating formulation is subjected to the setting conditions, at least to the extent that the confectionery coating is flowable until subjected to the setting conditions. In the '777 Application, the polyol is blended separately with the fat ingredient of a confectionery coating before being added to the remaining ingredients of the confectionery coating so that the confectionery coating remains flowable until subjected to setting conditions. The confectionery coating may be a chocolate coating whereby the fat ingredient, with which the polyol is blended, may be, for instance, cocoa butter or a partially hydrogenated soybean fat. However, a disadvantage of a process of producing a confectionery coating containing a structured fat emulsion claimed in the '777 Application is that it cannot be used in the normal chocolate manufacturing process because the polyol has to be blended separately with the fat ingredient of the chocolate before adding to the remaining ingredients.